Have you ever thought about sea level? Is the town where you live close to or above sea level?

Well, Mrs. Harris' students have been learning about New Zealand so that they can better understand the place where their pen pals live. Charles looked up Auckland on the computer and brought in this information the next day.

"Did you know that Auckland is 196 meters above sea level?" he shared with the class.

Mrs. Harris wrote
on the board.

This is a situation where a positive integer was written on the board. Do you know how to write the opposite of this integer?

This Concept is all about opposites of given integers. We will return to this dilemma at the end of the Concept.

Guidance

An
integer
is the set of whole numbers and its opposites. This means that every integer has an opposite integer.

Here is what the set looks like.

....-5, -4, -3, -2, -1, 0, 1, 2, 3, 4, 5...

You see that each integer has an opposite value and the three dots at each end means that the set of whole numbers continues indefinitely in both a positive and negative direction.

Example A

Example B

Example C

67 feet above sea level

Solution:

Now back to the dilemma from the beginning of the Concept.

Have you ever thought about sea level? Is the town where you live close to or above sea level?

Well, Mrs. Harris' students have been learning about New Zealand so that they can better understand the place where their pen pals live. Charles looked up Auckland on the computer and brought in this information the next day.

"Did you know that Auckland is 196 meters above sea level?" he shared with the class.

Mrs. Harris wrote
on the board.

This is a situation where a positive integer was written on the board. Do you know how to write the opposite of this integer?

To write this as an opposite we simply change the sign and use the same number.

becomes

This is our answer.

Vocabulary

Here are the vocabulary words in this Concept.

Integers

the set of whole numbers and their opposites

Negative Numbers

numbers that are less than zero

Positive Numbers

numbers that are greater than zero

Zero

is a part of the set of integers, but is neither positive or negative

Guided Practice

Here is one for you to try on your own.

On day one, the stock market rose 25 points. If the opposite happened on day three, what integer could we write to represent this situation?